The invention relates to the well drilling industry, particularly oil wells, and more particularly to apparatus for assisting introduction into the wellbore, through the drill pipe or tubing, of logging tools and other completion assemblies, such as chemical cutters, string shots, free point indicators, jet cutters, metal severing tools, split shot cutters, radial cutting torches, pipe recovery logs, temperature logs, noise logs, and perforating guns.
Modern drilling techniques make it possible to drill “extended reach” and “horizontal” wells to exploit fractured formations and to access isolated productive zones away from the vertical wells of a single drilling platform. In wells deviated beyond 60 degrees, special hardware is required to guide, push, or pump the logging tools or completion assembly toward the interval of line that is of interest. During use of a conventional, rigid, sinker bar, the logging tools or other completion assemblies must be forced to pass through the angle of deviation thereby causing problems related to the rigidity and length of the rigid sinker bar assembly.